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Date: Fri, 08 Jun 2007 19:00:13 +0200
From: Martin Peschke <mp3@de.ibm.com>
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Subject: Re: [RFC] [Patch 4/4] lock contention tracking slimmed down
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To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-kernel@vger.kernel.org, jbaron@redhat.com, rostedt@goodmis.org, billh@gnuppy.monkey.org, mingo@elte.hu, linux-s390@vger.kernel.org
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Peter Zijlstra wrote:
> I'm confused as to where the class->stat objects are initialised? Is
> that done in lock_stat_init()? If so, then you have a bug.

static struct lock_class lock_classes[MAX_LOCKDEP_KEYS];

I assume this gets us class structures containing all zeros, doesn't it?
Then class->stat is zeros as well, which is handled by lib/statistics.
(In this case, data gathering hasn't been turned on yet, and statistic_inc()
and similar functions don't access other areas of struct statistic.)

Martin